HIGHLIGHT: The seasonal mean NINO3.4 anomaly was -0.49 for MJJ2010, a huge decrease from AMJ(+0.06).
The CA method, acting on global MJJ2010 seasonal means as latest input forecasts the 3 mo running mean anomaly for Nino34, has 100% of its members in La Nina territory for the rest of the year. The forecast is about 0.6C colder than last month, down to -1.8 by late 2010, making it a strong La Nina
Weights have developed some from last month. A few years with high –ve weight!, but more so with high +ve weight. Note an exceptionally high positive weight (+0.25), now for 2005. OCN flavor is present: many +ve weights in recent years, but never seen a –ve weight for a recent year (2009) before.
Table 1. Inner products (IP; scaled such that the sum of absolute values is 100; not shown) and weights (Wgt multiplied by 100.) of each of the years to construct an analogue to the sequence of 12 consecutive overlapping 3-month periods defined as the base (currently the 12 overlapping seasons string JJA2009 thru MJJ2010). Years in the table are labeled by the year of the middle month of the most recent predictor season. Weights for 1956 and 2009 are less (by 50%) because only half the members use these years ("early" members use 1956, "late" members 2009). Data currently thru Jul 2010.
|
Year |
IP |
Wgt |
Year |
IP |
Wgt |
Year |
IP |
Wgt |
Year |
IP
|
Wgt |
Year |
IP |
Wgt |
Year |
IP |
Weigt |
|
1956 |
xx |
1 |
1966 |
xx |
2 |
1976 |
xx |
-9 |
1986 |
xx |
-13 |
1996 |
xx |
10 |
2006 |
xx |
11 |
|
1957 |
xx |
-6 |
1967 |
xx |
-4 |
1977 |
xx |
-5 |
1987 |
xx |
5 |
1997 |
xx |
-8 |
2007 |
xx |
15 |
|
1958 |
xx |
1 |
1968 |
xx |
-5 |
1978 |
xx |
-2 |
1988 |
xx |
8 |
1998 |
xx |
4 |
2008 |
xx |
6 |
|
1959 |
xx |
-6 |
1969 |
xx |
19 |
1979 |
xx |
5 |
1989 |
xx |
-2 |
1999 |
xx |
1 |
2009 |
xx |
-1 |
|
1960 |
xx |
-13 |
1970 |
xx |
9 |
1980 |
xx |
0 |
1990 |
xx |
10 |
2000 |
xx |
-4 |
2010 |
xx |
NA |
|
1961 |
xx |
-6 |
1971 |
xx |
5 |
1981 |
xx |
-3 |
1991 |
xx |
-1 |
2001 |
xx |
4 |
xx |
Xx |
|
|
1962 |
xx |
5 |
1972 |
xx |
-7 |
1982 |
xx |
4 |
1992 |
xx |
1 |
2002 |
xx |
7 |
xx |
Xx |
|
|
1963 |
xx |
-4 |
1973 |
xx |
14 |
1983 |
xx
|
3 |
1993 |
xx |
-3 |
2003 |
xx |
5 |
xx |
Xx |
|
|
1964 |
xx |
1 |
1974 |
xx |
4 |
1984 |
xx |
-9 |
1994 |
xx |
-18 |
2004 |
xx |
1 |
xx |
Xx |
|
|
1965 |
xx |
-15 |
1975 |
xx |
3 |
1985 |
xx |
1 |
1995 |
xx |
8 |
2005 |
xx |
25 |
xx |
Xx |
Weights are high +ve (>+0.10) for 2007,2006,2005,1996,1990,1973,1969. Weights are high -ve (< - 0.10) for 1994,1986,1965,1960.
Ens ave Nino34 anomaly forecasts, for leads -3, -2, -1, 0 etc: in plain numbers (ensemble mean):
|
-0.49 |
-0.52 |
-0.71 |
-1.08 |
-1.33 |
-1.63 |
-1.83 |
-1.83 |
-1.63 |
-1.19 |
-0.75 |
-0.37 |
-0.15 |
-0.01 |
0.13 |
0.24 |
0.34 |
0.36 |
0.3 |
0.18 |
0.07 |
|
MJJ |
JAS |
SON |
NDJ |
JFM11 |
MAM |
MJJ |
JAS |
SON |
NDJ |
JFM12 |
One month ago:
|
0.06 |
0.02 |
-0.1 |
-0.29 |
-0.43 |
-0.6 |
-0.84 |
-1.06 |
-1.17 |
-1.14 |
-0.92 |
-0.66 |
-0.45 |
-0.33 |
-0.27 |
-0.15 |
-0.07 |
-0.01 |
-0.06 |
-0.15 |
-0.24 |
|
MJJ |
JAS |
SON11 |
NDJ |
JFM11 |
MAM |
MJJ |
JAS |
SON |
NDJ |
Two months ago:
|
0.59 |
0.46 |
0.17 |
-0.23 |
-0.37 |
-0.51 |
-0.66 |
-0.88 |
-1.08 |
-1.15 |
-1.08 |
-0.84 |
-0.58 |
-0.38 |
-0.25 |
-0.2 |
-0.06 |
0.04 |
0.14 |
0.13 |
0.04 |
|
MAM10 |
MJJ |
JAS |
SON |
NDJ |
JFM |
MAM11 |
MJJ |
JAS |
SON11 |
NDJ |
Three months ago:
|
1.01 |
0.81 |
0.36 |
-0.21 |
-0.42 |
-0.57 |
-0.71 |
-0.83 |
-1.01 |
-1.15 |
-1.15 |
-1.03 |
-0.74 |
-0.45 |
-0.23 |
-0.06 |
0.02 |
0.19 |
0.33 |
0.46 |
0.49 |
|
MAM |
MJJ |
JAS10 |
SON |
NDJ |
JFM11 |
MAM |
MJJ |
JAS11 |
SON |
Four months ago:
|
1.29 |
1.11 |
0.62 |
-0.07 |
-0.26 |
-0.43 |
-0.56 |
-0.69 |
-0.77 |
-0.89 |
-0.97 |
-0.94 |
-0.81 |
-0.56 |
-0.29 |
-0.11 |
0.04 |
0.1 |
0.27 |
0.41 |
0.53 |
|
JFM10 |
MAM |
MJJ |
JAS |
SON |
NDJ |
JFM11 |
MAM |
MJJ |
JAS |
SON11 |
Anomalies relative to
1971-2000 climo.